Valve actuators are utilized in a wide variety of hydraulic and pneumatic systems to adjust the position of a valve element within a flow passage and thereby regulate fluid flow therethrough. When deployed on a vehicle, it is often desirable for a valve actuator to provide a relatively high torque output while simultaneously having a compact and lightweight package. When deployed on a submarine, in particular, it is further desirable that such a valve actuator operates in an exceptionally quiet and reliable manner. High power hydraulic actuators are routinely employed to achieve these goals. However, high power hydraulic actuators typically require fluid connection to a remote hydraulic source via a plumbing network. Not only do such plumbing networks pose potential fluid leakage problems, but they add undesirable cost, weight, and volume to the overall system.
Accordingly, it is desirable to provide a low profile valve actuator that provides a relatively high torque output. Preferably, such a low profile valve actuator would be mechanically balanced so as to reduce component stress and thereby improve reliability and operational life. It would also be desirable if, in certain embodiments, the valve actuator were electromechanical and thus did not require plumbing of the type commonly associated with conventional high power hydraulic actuators. Finally, in embodiments intended for deployment aboard a submarine, it would be desirable for such a low profile valve actuator to operate in a quiet manner. Other desirable features and characteristics of the present invention will become apparent from the subsequent Detailed Description and the appended claims, taken in conjunction with the accompanying drawings and this Background.